Using a mobile telephone means that the user is always available to be contacted, but people often go through periods in their day when they do not wish to be disturbed. An example of this is when the user is already in an active conversation face-to-face with another person. As well as being a problem for general phone users, there are specific social situations where the user may wish to be contacted, but only if the user is not currently conversing. For example, an estate agent showing customers around houses will often receive calls, but in general, the estate agent will want to prioritize the face-to-face conversation over any incoming call because the estate agent is trying to make a sale. One way to avoid being interrupted is by manually changing the settings on a user's mobile phone, by, for example, putting the phone in a silent mode.